US5511433A - Pipette device - Google Patents

Pipette device Download PDF

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Publication number
US5511433A
US5511433A US07/991,475 US99147592A US5511433A US 5511433 A US5511433 A US 5511433A US 99147592 A US99147592 A US 99147592A US 5511433 A US5511433 A US 5511433A
Authority
US
United States
Prior art keywords
piston
cylinder
housing
shell
support
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US07/991,475
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English (en)
Inventor
Horst Sabloewski
Ingo Cordes
Jochen Beese
Klaus Schurbrock
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eppendorf SE
Original Assignee
Eppendorf Netheler Hinz GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eppendorf Netheler Hinz GmbH filed Critical Eppendorf Netheler Hinz GmbH
Priority to US07/991,475 priority Critical patent/US5511433A/en
Application granted granted Critical
Publication of US5511433A publication Critical patent/US5511433A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/02—Burettes; Pipettes
    • B01L3/021—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
    • B01L3/0217—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids of the plunger pump type
    • B01L3/0224—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids of the plunger pump type having mechanical means to set stroke length, e.g. movable stops

Definitions

  • the present invention refers to a pipette device, comprising a housing, an actuating element projecting from the upper end of said housing for depressing the actuating element against a spring force, further comprising a cylinder, a hollow piston moveable in said cylinder for displacing an air volume, said piston being connected to said actuating element by a rod, and comprising a support, an adapter cone for receiving replaceable pipette tips communicating with said cylinder, said hollow piston comprising an outer shell mounted on said support preferrably made of plastic material.
  • the German application referred to discloses an improvement of known pipette devices to facilitate the handling and to reduce the force which is necessary to operate the device.
  • the piston of this pipette is solid and shaped as a rod which tightly enters a cylinder which opens towards an adapter cone on which a pipette tip is placed.
  • the rod shaped piston is suited to take up very small volume, the piston diameter being in the range of 1 to 5 mm.
  • the European application improves the calibration of a pipette and discloses an embodiment in which the piston is connected to a piston rod through a connecting member which is shaped as a rod of a small cross section.
  • the connecting member allows to make the rod and the piston of different materials.
  • the present invention refers to a pipette device comprising a piston of a cross section which is larger than the tubular passage to the adapter cone.
  • This structure facilitates handling varying pipetting volume in providing an individual cylinder chamber above the tubular passage to the adapter cone.
  • the piston is adjustably mounted in the cylinder to take up different pipetting volume. Accordingly, the piston stroke is adjusted by setting the piston initially to a predetermined position.
  • a pipetting device of the type above referred to is shown by German specification 1 952 774.
  • the piston of this pipette device comprises a projection and an annular seal cooperating with the cylinder wall.
  • the projection is provided with a fluorocarbon sleeve which is cemented thereon or tightly pressed on. This is an expensive manufacturing step and relative changes in position of the sleeve and projection cannot be excluded over an extended time of use resulting in decreasing the pipetting accuracy. Furthermore, vibrations or impacts transferred from the actuating button are detrimental to the calibration of the pipetting volume.
  • the piston cannot be guided in a tight and sealing engagement with the cylinder wall so that the sealing ring additionally Serves to make up for the piston play.
  • the wear of the sealing ring is relatively high.
  • the material of the piston cannot be suited to different substances to be handled with the pipette which must be replaced as a whole when the wear of the piston becomes excessive.
  • the piston is hollow and comprises an outer shell mounted on a support.
  • the shell is tubular in shape and annular seals are provided on the support cooperating with the inner wall of the shell plugged on the support.
  • a disk shaped element is provided to cover a lower opening of the shell to maintain the shell in position on the support.
  • a hollow piston comprising a precision shell is a greatly improved embodiment as the outer piston wall may be greatly reduced, as a steel shell may be used for example which results in a very small wall thickness of the piston.
  • the piston sleeve or, respectively piston shell may be easily replaced to suit different substances to be handled.
  • the shell is maintained in position by the disk shaped element.
  • the sealing rings In combination with the annular seals replacing the shell and assembling the piston is facilitated, the sealing rings further compensating for dimensions and tolerances and allowing the piston to adjust with respect to the cylinder wall.
  • the shell is made of a ceramic mass to handle liquids containing agressive gases, acids or other agressive liquid of high vapour pressure.
  • a coupling for removable mounting the rod to the support and wherein the coupling comprises a supporting surface for the upper end of the shell and wherein the support is removable mounted on the coupling and the diameter of the support is selected according to the wall thickness of the shell which results in an easy replacement of the piston. Any differences in diameter are compensated for by selecting sealing rings of varying thickness. Still further the structure according to the invention allows to replace the shell as well as the support.
  • the support, the actuating rod and the disk shaped element may be an integral structure.
  • the embodiment according to the invention further allows to provide a rather small play between the piston and the cylinder wherein the difference between the diameters of the cylinder and the piston is in a range of 0.4 mm.
  • This advantage is substantial in order to avoid that gases and air of different temperatures are mixed which air and gas originates from the handle portion on the one hand and from the working tip on the other hand.
  • FIGS. 1 to 3 three sections of a pipette device illustrating a side section of the pipette device when placed one to the other lengthwise at A--A and B--B.
  • FIG. 4 a part view of the pipette device illustrating a special element in an enlarged scale showing a particular embodiment.
  • the pipette device shown in FIGS. 1 to 3 comprises a housing 1 which may be composed of a number of portions, but is numbered 1 throughout.
  • actuating button 2 which is moveable against a spring 3 as well as rotatable to vary the volume of the pipette device by setting and driving means 4.
  • a spindle 6 is rotated through sleeves 5 in order to forwardly displace a rod 7.
  • the lower end of the rod carries a connecting piece 8 including a support 9 for a piston 10.
  • This piston may be displaced in a cylinder 11 from which a tube-like connection 12 leads to a connecting cone 13.
  • the spring 14 shown in FIG. 1 serves to return the actuating button.
  • the spring 15 serves to return the piston to its normal position and, in particular, to maintain the connection between a holding means, for example a magnet 16 and a moveable counter magnet element 17.
  • the spring 18 serves to urge a lower sleeve 19 for the piston 10 to an internal conical face 21 of the housing 1 through a resilient sealing ring 20.
  • the spring 18 may be replaced by a sleeve.
  • FIG. 3 shows a structure which is not the subject of the invention providing an axially moveable sleeve 22 which is suited to release containers pushed on.
  • the piston 10 is a hollow piston.
  • the piston comprises an outer tube-like shell 23 and an inner support 9 made of a heat insulating plastic material including a pair of annular grooves 24, 25 for accommodating annular seals 26, 27.
  • the seals may be rubber seals or resistant elastic plastic seals.
  • the seals guide the shell 23 which has a sliding seat on the support 9 according to a particular embodiment of the invention.
  • the support is connected to the connecting piece 8 by means of a projection 28 screwed on or plugged in.
  • the connecting piece 8 is particularly made of a heat insulating material. It may be resilient and carries an outward flange 29 for supporting the upper edge of the tubular shell 23.
  • the connecting piece comprises an upwardly directed sleeve 40 including inwardly facing axial webs 39 between peripheral slots, the webs 39 fitting to the rod and defining a matching connection.
  • the connection is improved by an outer, in particular metallic clamp 41 which may be releasably mounted when changing the plugging connection between the projection 28 and a lower suspending portion 42 of the connecting piece, and, is not sufficient for a safe connection on the one hand, but for a releasable connection on the other hand.
  • the lower edge of the tubular shell is held on the support 9 by a preferrably disk shaped element 30 which is secured to the support 9.
  • FIG. 4 shows a one-piece embodiment of the support 9 and rod 7.
  • the thickness of the shell 23 may be selected such that it can be made of ceramic material.
  • the shell may be replaced by removing the coupling 8 from the support 9. Access is provided by unscrewing a threading connection 33 between an upper handle portion 31 and a lower pipette portion 32. While FIG. 2 shows a relatively thick walled shell, it may be replaced by a metal casing of a very thin thickness.
  • the difference between the inner diameter 34 of the cylinder 11 and the outer diameter 35 of the piston 10 can be selected very small, preferrably in the range of 0.4 mm.
  • FIG. 4 shows a disk shaped element 30 integral with the support 9 projecting from the rod 7.
  • the support 9 carries the sealing rings 26 and 27.
  • the upper support For mounting the shell not shown in FIG. 4 the upper support must be removed.
  • a flange 38 may be threaded on an extension 36 provided with a thread 37.
  • the shell has to be replaced from above.
  • FIG. 4 shows a further particularity for the seal 26 which is integrally formed on the support 9. The same applies for the seal 27.
  • the integral element shown in FIG. 4 is made of a plastic material suitable for sealing and having sufficient strength.

Landscapes

  • Health & Medical Sciences (AREA)
  • Clinical Laboratory Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Devices For Use In Laboratory Experiments (AREA)
  • Catching Or Destruction (AREA)
  • Sampling And Sample Adjustment (AREA)
  • Endoscopes (AREA)
  • Pipe Accessories (AREA)
US07/991,475 1990-05-04 1992-12-16 Pipette device Expired - Lifetime US5511433A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US07/991,475 US5511433A (en) 1990-05-04 1992-12-16 Pipette device

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE4014333A DE4014333A1 (de) 1990-05-04 1990-05-04 Pipettiervorrichtung
DE4014333.3 1990-05-04
US69423491A 1991-05-01 1991-05-01
US07/991,475 US5511433A (en) 1990-05-04 1992-12-16 Pipette device

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US69423491A Continuation 1990-05-04 1991-05-01

Publications (1)

Publication Number Publication Date
US5511433A true US5511433A (en) 1996-04-30

Family

ID=6405711

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/991,475 Expired - Lifetime US5511433A (en) 1990-05-04 1992-12-16 Pipette device

Country Status (5)

Country Link
US (1) US5511433A (de)
EP (1) EP0455043B1 (de)
JP (1) JPH0655278B2 (de)
AT (1) ATE122930T1 (de)
DE (2) DE4014333A1 (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1230979A2 (de) * 2001-02-09 2002-08-14 Biohit Oy Pipette mit einstellbarem Volumen
US20030099578A1 (en) * 2001-10-16 2003-05-29 Richard Cote Hand-held pipettor
US20050158211A1 (en) * 2004-01-16 2005-07-21 Piacenza Donna A. Pipette device with pivotable nozzle assembly
US20050262951A1 (en) * 2004-05-27 2005-12-01 Richard Cote Hand held pipette
US20060027033A1 (en) * 2002-10-16 2006-02-09 Richard Cote Hand-held pipette employing voice recognition control
US20080199361A1 (en) * 2007-02-16 2008-08-21 Francis Gomes Hand-held pipetting device
US20090010809A1 (en) * 2007-07-03 2009-01-08 Hadjis Peter T Manual pipette filler
US20090007701A1 (en) * 2007-07-03 2009-01-08 Hadjis Peter T Pivoting pipette device
US8398934B2 (en) * 2007-10-16 2013-03-19 Ivek Corporation Coupling system for use with fluid displacement apparatus
US20130233054A1 (en) * 2012-03-09 2013-09-12 Torion Technologies, Inc. Needle trap for use with a gas chromatograph-mass spectrometer for field sampling and analysis
CN103447104A (zh) * 2012-02-07 2013-12-18 埃佩多夫股份公司 移液器
US20150217289A1 (en) * 2014-02-04 2015-08-06 Austen Biolnnovation Institute in Akron Plunger for low-volume syringe pipette
US9358538B2 (en) 2012-04-30 2016-06-07 The Regents Of The University Of Michigan High resolution pipette
US9527075B2 (en) 2012-11-05 2016-12-27 Austen Bioinnovation Institute In Akron Low-volume syringe pipette
CN113877647A (zh) * 2020-07-02 2022-01-04 埃佩多夫股份公司 多通道移液头

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI88775C (fi) * 1992-02-11 1993-07-12 Biohit Oy Pipett
DE4209620C1 (de) * 1992-03-25 1993-12-16 Eppendorf Geraetebau Netheler Verfahren zur Korrektur des Volumenfehlers ïV bei einem Pipettiersystem
DE4335863C1 (de) * 1993-10-21 1995-02-02 Eppendorf Geraetebau Netheler Kolbenhubpipette
US5454268A (en) * 1993-11-15 1995-10-03 Kim; Young S. Double-plunger liquid displacement syringe pipet
PL214640B1 (pl) * 2009-04-30 2013-08-30 Pz Htl Spolka Akcyjna Zespól trzonu do zamontowania w pipecie mechanicznej lub elektronicznej
EP4331725A1 (de) * 2022-08-30 2024-03-06 Eppendorf SE Kolbenstange und verfahren zur herstellung einer solchen kolbenstange

Citations (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE858148C (de) * 1943-03-27 1952-12-04 Josef Gries Vorrichtung zum Ansaugen einer fuer die Bestimmung der Blutsenkung erforderlichen Blutmenge
US3506164A (en) * 1968-05-31 1970-04-14 Sherwood Medical Ind Inc Automatic pipette
DE1952774A1 (de) * 1968-10-25 1970-07-02 Bio Dynamics Inc Pipette
DE1598165A1 (de) * 1967-01-19 1971-10-14 Brand Fa Rudolf Pipettierhilfegeraet
US3732735A (en) * 1971-06-17 1973-05-15 Medical Laboratory Automation Pipettes
US3853012A (en) * 1971-10-04 1974-12-10 Medical Laboratory Automation Pipettes
US3901413A (en) * 1974-03-01 1975-08-26 Precision Sampling Corp High pressure syringe
US3918308A (en) * 1973-04-16 1975-11-11 Oxford Lab Liquid transfer pipetting device with a tip ejector
DE2525713A1 (de) * 1974-06-24 1976-01-15 Mediplast Ab Vorrichtung zur ueberfuehrung von blut oder einer aehnlichen fluessigkeit in eine pipette
SU542547A1 (ru) * 1974-09-12 1977-01-15 Институт Биохимии И Физиологии Микроорганизмов Ан Ссср Пипетка
DE2549477A1 (de) * 1975-11-05 1977-05-12 Eppendorf Geraetebau Netheler Pipettiervorrichtung
DE2720669A1 (de) * 1976-05-10 1977-12-22 Marteau D Autry Eric Einstellbare verduennungsvorrichtung
DE2651333A1 (de) * 1976-11-10 1978-05-11 Sarstedt Kunststoff Saugpipette
US4399712A (en) * 1981-02-09 1983-08-23 Nichiryo Co., Ltd. Semi-automatic electro-mechanical pipette with controlled tip remover
US4616514A (en) * 1983-06-06 1986-10-14 Rainin Instrument Co., Inc. Replaceable tip assembly for pipette
US4625572A (en) * 1984-04-18 1986-12-02 Kabushiki Kaisha Toshiba Cylinder pump
EP0364621A1 (de) * 1988-10-21 1990-04-25 Eppendorf-Netheler-Hinz Gmbh Pipettiervorrichtung

Patent Citations (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE858148C (de) * 1943-03-27 1952-12-04 Josef Gries Vorrichtung zum Ansaugen einer fuer die Bestimmung der Blutsenkung erforderlichen Blutmenge
DE1598165A1 (de) * 1967-01-19 1971-10-14 Brand Fa Rudolf Pipettierhilfegeraet
US3506164A (en) * 1968-05-31 1970-04-14 Sherwood Medical Ind Inc Automatic pipette
DE1952774A1 (de) * 1968-10-25 1970-07-02 Bio Dynamics Inc Pipette
US3646817A (en) * 1968-10-25 1972-03-07 Bio Dynamics Inc Pipette
US3732735A (en) * 1971-06-17 1973-05-15 Medical Laboratory Automation Pipettes
US3853012A (en) * 1971-10-04 1974-12-10 Medical Laboratory Automation Pipettes
US3918308A (en) * 1973-04-16 1975-11-11 Oxford Lab Liquid transfer pipetting device with a tip ejector
US3901413A (en) * 1974-03-01 1975-08-26 Precision Sampling Corp High pressure syringe
DE2525713A1 (de) * 1974-06-24 1976-01-15 Mediplast Ab Vorrichtung zur ueberfuehrung von blut oder einer aehnlichen fluessigkeit in eine pipette
US4037464A (en) * 1974-06-24 1977-07-26 Mediplast Ab Device for transferring blood or a similar fluid to a pipette
SU542547A1 (ru) * 1974-09-12 1977-01-15 Институт Биохимии И Физиологии Микроорганизмов Ан Ссср Пипетка
FR2330456A1 (fr) * 1975-11-05 1977-06-03 Eppendorf Geraetebau Netheler Dispositif de pipetage
DE2549477A1 (de) * 1975-11-05 1977-05-12 Eppendorf Geraetebau Netheler Pipettiervorrichtung
US4041764A (en) * 1975-11-05 1977-08-16 Eppendorf Geratebau Netheler & Hinz Gmbh Pipette device
DE2720669A1 (de) * 1976-05-10 1977-12-22 Marteau D Autry Eric Einstellbare verduennungsvorrichtung
US4141250A (en) * 1976-05-10 1979-02-27 Marteau D Autry Eric Plural piston, adjustable diluting device having a volume indicator assembly
DE2651333A1 (de) * 1976-11-10 1978-05-11 Sarstedt Kunststoff Saugpipette
US4133211A (en) * 1976-11-10 1979-01-09 Sarstedt W Suction pipette
US4399712A (en) * 1981-02-09 1983-08-23 Nichiryo Co., Ltd. Semi-automatic electro-mechanical pipette with controlled tip remover
US4616514A (en) * 1983-06-06 1986-10-14 Rainin Instrument Co., Inc. Replaceable tip assembly for pipette
US4625572A (en) * 1984-04-18 1986-12-02 Kabushiki Kaisha Toshiba Cylinder pump
EP0364621A1 (de) * 1988-10-21 1990-04-25 Eppendorf-Netheler-Hinz Gmbh Pipettiervorrichtung
US5012682A (en) * 1988-10-21 1991-05-07 Firma Eppendorf-Netheler-Hinz Gmbh Pipetting device

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1230979A2 (de) * 2001-02-09 2002-08-14 Biohit Oy Pipette mit einstellbarem Volumen
EP1230979A3 (de) * 2001-02-09 2003-10-29 Biohit Oyj Pipette mit einstellbarem Volumen
US20030099578A1 (en) * 2001-10-16 2003-05-29 Richard Cote Hand-held pipettor
US8088342B2 (en) 2001-10-16 2012-01-03 Matrix Technologies Corporation Hand-held pipettor
US6923938B2 (en) 2001-10-16 2005-08-02 Matrix Technologies Corporation Hand-held pipettor
US20060027033A1 (en) * 2002-10-16 2006-02-09 Richard Cote Hand-held pipette employing voice recognition control
US7381371B2 (en) 2004-01-16 2008-06-03 Heathrow Scientific Llc Pipette device with pivotable nozzle assembly
US20050158211A1 (en) * 2004-01-16 2005-07-21 Piacenza Donna A. Pipette device with pivotable nozzle assembly
US7284454B2 (en) 2004-05-27 2007-10-23 Matrix Technologies Corporation Hand held pipette
US20050262951A1 (en) * 2004-05-27 2005-12-01 Richard Cote Hand held pipette
US20080199361A1 (en) * 2007-02-16 2008-08-21 Francis Gomes Hand-held pipetting device
US20090010809A1 (en) * 2007-07-03 2009-01-08 Hadjis Peter T Manual pipette filler
US20090007701A1 (en) * 2007-07-03 2009-01-08 Hadjis Peter T Pivoting pipette device
US8398934B2 (en) * 2007-10-16 2013-03-19 Ivek Corporation Coupling system for use with fluid displacement apparatus
CN103447104B (zh) * 2012-02-07 2016-05-18 埃佩多夫股份公司 移液器
CN103447104A (zh) * 2012-02-07 2013-12-18 埃佩多夫股份公司 移液器
US20130233054A1 (en) * 2012-03-09 2013-09-12 Torion Technologies, Inc. Needle trap for use with a gas chromatograph-mass spectrometer for field sampling and analysis
US9322750B2 (en) * 2012-03-09 2016-04-26 Torion Technologies, Inc. Needle trap for use with a gas chromatograph-mass spectrometer for field sampling and analysis
US9358538B2 (en) 2012-04-30 2016-06-07 The Regents Of The University Of Michigan High resolution pipette
US9527075B2 (en) 2012-11-05 2016-12-27 Austen Bioinnovation Institute In Akron Low-volume syringe pipette
WO2015120053A1 (en) * 2014-02-04 2015-08-13 Austen Bioinnovation Institute In Akron Plunger for low-volume syringe pipette
US20150217289A1 (en) * 2014-02-04 2015-08-06 Austen Biolnnovation Institute in Akron Plunger for low-volume syringe pipette
US10076750B2 (en) * 2014-02-04 2018-09-18 Austen Bioinnovation Institute In Akron Plunger for low-volume syringe pipette
CN113877647A (zh) * 2020-07-02 2022-01-04 埃佩多夫股份公司 多通道移液头
CN113877647B (zh) * 2020-07-02 2023-07-21 埃佩多夫欧洲股份公司 多通道移液头

Also Published As

Publication number Publication date
DE4014333A1 (de) 1991-11-28
EP0455043A2 (de) 1991-11-06
JPH0655278B2 (ja) 1994-07-27
JPH04227859A (ja) 1992-08-17
DE4014333C2 (de) 1992-07-02
ATE122930T1 (de) 1995-06-15
DE59105556D1 (de) 1995-06-29
EP0455043A3 (en) 1992-02-26
EP0455043B1 (de) 1995-05-24

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